U.S. patent number 9,441,470 [Application Number 13/903,144] was granted by the patent office on 2016-09-13 for self-locating downhole devices.
This patent grant is currently assigned to Schlumberger Technology Corporation. The grantee listed for this patent is Schlumberger Technology Corporation. Invention is credited to Billy Anthony, Michael J. Bertoja, Julio C. Guerrero, Christopher Hopkins, Christian Ibeagha, Bruno Lecerf, Alex Moody-Stuart, Adam Mooney, Dinesh Patel, Adam Paxson, Jay Russell, Gary L. Rytlewski.
United States Patent |
9,441,470 |
Guerrero , et al. |
September 13, 2016 |
Self-locating downhole devices
Abstract
A technique that is usable with a well includes deploying a
plurality of location markers in a passageway of the well and
deploying an untethered object in the passageway such that the
object travels downhole via the passageway. The technique includes
using the untethered object to sense proximity of at least some of
the location markers as the object travels downhole, and based on
the sensing, selectively expand its size to cause the object to
become lodged in the passageway near a predetermined location.
Inventors: |
Guerrero; Julio C. (Cambridge,
MA), Rytlewski; Gary L. (League City, TX), Lecerf;
Bruno (Houston, TX), Bertoja; Michael J. (Bellaire,
TX), Ibeagha; Christian (Missouri City, TX),
Moody-Stuart; Alex (London, GB), Mooney; Adam
(Missouri City, TX), Russell; Jay (Houston, TX), Hopkins;
Christopher (Houston, TX), Paxson; Adam (Boston, MA),
Anthony; Billy (Missouri City, TX), Patel; Dinesh (Sugar
Land, TX) |
Applicant: |
Name |
City |
State |
Country |
Type |
Schlumberger Technology Corporation |
Sugar Land |
TX |
US |
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Assignee: |
Schlumberger Technology
Corporation (Sugar Land, TX)
|
Family
ID: |
44992363 |
Appl.
No.: |
13/903,144 |
Filed: |
May 28, 2013 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20130255963 A1 |
Oct 3, 2013 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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13112512 |
May 20, 2011 |
8505632 |
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12945186 |
Nov 12, 2010 |
8276674 |
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11834869 |
Aug 7, 2007 |
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10905073 |
Dec 14, 2004 |
7387165 |
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61347360 |
May 21, 2010 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B
43/119 (20130101); E21B 43/26 (20130101); E21B
33/12 (20130101); E21B 34/06 (20130101); E21B
43/08 (20130101); E21B 47/04 (20130101); E21B
47/09 (20130101); E21B 34/14 (20130101); E21B
43/14 (20130101); E21B 2200/06 (20200501) |
Current International
Class: |
E21B
34/14 (20060101); E21B 43/26 (20060101); E21B
43/14 (20060101); E21B 34/06 (20060101); E21B
47/09 (20120101); E21B 43/08 (20060101); E21B
33/12 (20060101); E21B 43/119 (20060101); E21B
47/04 (20120101); E21B 34/00 (20060101) |
Field of
Search: |
;166/373,313,386,332.4,193,194,254.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Andrews; David
Attorney, Agent or Firm: Peterson; Jeffrey R.
Parent Case Text
The present application is a continuation of U.S. patent
application Ser. No. 13/112,512 (now U.S. Pat. No. 8,505,632),
entitled, "Method and Apparatus for Deploying an Using
Self-Locating Downhole Devices" which was filed May 20, 2011, which
claims the benefit under 35 U.S.C. .sctn.119(e) to U.S. Provisional
Patent Application Ser. No. 61/347,360, entitled, "MECHANISMS FOR
DEPLOYING SELF-LOCATING DOWNHOLE DEVICES," which was filed on May
21, 2010, and is hereby incorporated by reference in its entirety;
and is a continuation-in-part of U.S. patent application Ser. No.
12/945,186 (now U.S. Pat. No. 8,276,674), entitled, "SYSTEM FOR
COMPLETING MULTIPLE WELL INTERVALS," which was filed on Nov. 12,
2010, which is a continuation of U.S. patent application Ser. No.
11/834,869 (now abandoned), entitled, "SYSTEM FOR COMPLETING
MULTIPLE WELL INTERVALS," which was filed on Aug. 7, 2007, and is a
divisional of U.S. Pat. No. 7,387,165, entitled, "SYSTEM FOR
COMPLETING MULTIPLE WELL INTERVALS," which issued on Jun. 17, 2008.
Claims
What is claimed is:
1. A method usable with a well, comprising: deploying a plurality
of landmarks in a passageway of the well; deploying an untethered
object in the passageway such that the object travels downhole via
the passageway, wherein the untethered object comprises an
electromagnetic antenna; and using the antenna of the untethered
object to sense proximity of at least one of the landmarks as the
object travels downhole and based on the sensing, selectively
expand its size to cause the object to become lodged in the
passageway near a predetermined location.
2. The method of claim 1, further comprising: using the object to
dislodge itself from the passageway in response to the object
determining that a predetermined time interval has elapsed after
the object became lodged in the passageway.
3. The method of claim 1, further comprising: while the object is
traveling downhole, using the object to determine a velocity of the
object based at least in part on the sensing of said at least one
landmark and estimate when the object is to arrive near the
predetermined location based at least in part on the determined
velocity.
4. The method of claim 1, further comprising: using the object to
recognize the at least one landmark by transmitting a signal to
interrogate a radio frequency tag associated with the landmark.
5. The method of claim 1, wherein the act of deploying the landmark
comprise deploying identifiers near portions of the passageway
where the passageway is restricted in size.
6. The method of claim 1, further comprising actuating a motor to
rotate a plurality of sealing elements to radially expand the
object.
7. The method of claim 1, further comprising: pressurizing a region
in the passageway when the object is lodged to operate a flow
control valve or operate a valve adapted to, when open, establish
fluid communication between a well bore and a formation.
8. The method of claim 1, further comprising: pressurizing a region
in the passageway when the object is lodged to operate a
perforating gun.
9. The method of claim 1, further comprising: radially contracting
the object to dislodge the object from the passageway; and reverse
flowing the object out of the passageway.
10. The method of claim 1, further comprising: radially contracting
the object to dislodge the object from the passageway, allowing the
object to be moved further into the passageway from said point near
the predetermined location.
11. The method of claim 1, wherein the act of using the untethered
object comprises using the untethered object to estimate when the
untethered object arrives at the predetermined location and
regulate its expansion based on the estimate.
12. An apparatus usable with a well, comprising: a body adapted to
travel downhole untethered via a passageway of the well; a blocker
adapted to travel downhole with the body in a contracted state as
the body travels in the passageway, and be selectively radially
expanded to lodge the body in the passageway; a sensor comprising a
signal generator adapted to travel downhole with the body and sense
at least one of a plurality of landmarks disposed along the
passageway as the body travels downhole, the signal generator
driving an electromagnetic antenna; and a controller adapted to:
travel downhole with the body; based on the sensing, control the
blocker to cause the blocker to radially expand as the body is
traveling to cause the body to lodge in the passageway near the
predetermined location.
13. The apparatus of claim 12, wherein the blocker is adapted to
anchor the body and seal off the passageway near the predetermined
location.
14. The apparatus of claim 12, wherein the controller is adapted to
control the blocker to dislodge the body from the passageway in
response to the controller determining that a predetermined time
interval has elapsed after the body became lodged in the
passageway.
15. The apparatus of claim 12, wherein the controller is adapted to
determine a velocity of the object based at least in part on the
sensing of said at least one landmark and estimate when the object
is to arrive near the predetermined location based at least in part
on the determined velocity.
16. The apparatus of claim 12, wherein the sensor comprises a radio
frequency identification tag reader.
17. The apparatus of claim 12, further comprising an actuator,
wherein: the blocker comprises a plurality of fingers and a plate
to establish a groove and pin relationship with the fingers to
radially expand the fingers, and the controller is adapted to
energize the motor to cause the motor to rotate the plate relative
to the fingers to radially expand the fingers.
18. The apparatus of claim 12, wherein the body is adapted to lodge
in a control sleeve of the valve such that pressurization of a
region in the passageway when the body is lodged in the control
sleeve changes a state of a flow control valve.
19. The apparatus of claim 12, further comprising: a perforating
gun attached to the body, the perforating gun being adapted to fire
perforating charges in response to pressurization of a region in
the passageway when the body is lodge in the passageway.
20. The apparatus of claim 12, wherein the controller is adapted to
selectively control the blocker to radially contract the blocker to
dislodge the body from the passageway.
21. The apparatus of claim 12, wherein the body comprises a housing
to at least partially contain the blocker, the sensor and the
controller, and the housing is adapted to be removed by a milling
tool to remove the body when lodged in the passageway.
22. A system usable with a well, comprising: a casing string
adapted to support a wellbore of the well, the casing string
comprising a passageway; a plurality of landmarks deployed along
the passageway; and a plug to travel downhole untethered via the
passageway, the plug adapted to: electromagnetically sense and
recognize at least one of the landmarks as the plug travels
downhole, estimate when the plug is to arrive near a predetermined
location in the well based at least in part on recognition of said
at least one landmarks, and selectively expand its size to cause
the plug to become lodged in the passageway near the predetermined
location.
Description
TECHNICAL FIELD
The invention generally relates to a technique and apparatus for
deploying and using self-locating downhole devices.
BACKGROUND
For purposes of preparing a well for the production of oil or gas,
at least one perforating gun may be deployed into the well via a
deployment mechanism, such as a wireline or a coiled tubing string.
The shaped charges of the perforating gun(s) are fired when the
gun(s) are appropriately positioned to perforate a casing of the
well and form perforating tunnels into the surrounding formation.
Additional operations may be performed in the well to increase the
well's permeability, such as well stimulation operations and
operations that involve hydraulic fracturing. All of these
operations typically are multiple stage operations, which means
that the operation involves isolating a particular zone, or stage,
of the well, performing the operation and then proceeding to the
next stage. Typically, a multiple stage operation involves several
runs, or trips, into the well.
Each trip into a well involves considerable cost and time.
Therefore, the overall cost and time associated with a multiple
stage operation typically is a direct function of the number of
trips into the well used to complete the operation.
SUMMARY
In an embodiment of the invention, a technique that is usable with
a well includes deploying a plurality of location markers in a
passageway of the well and deploying an untethered object in the
passageway such that the object travels downhole via the
passageway. The technique includes using the untethered object to
sense proximity to some of a plurality of location markers as the
object travels downhole and based on the sensing, selectively
expand its size to cause the object to become lodged in the
passageway near a predetermined location.
In another embodiment of the invention, an apparatus that is usable
with a well includes a body adapted to travel downhole untethered
via a passageway of the well, a blocker, a sensor and a controller.
The blocker is adapted to travel downhole with the body, be
contracted as the body travels in the passageway, and be
selectively radially expanded to lodge the both in the passageway.
The sensor is adapted to travel downhole with the body and sense at
least some of a plurality of location markers, which are disposed
along the passageway as the body travels downhole. The controller
is adapted to travel downhole with the body and based on the
sensing, control the blocker to cause the blocker to radially
expand as the body is traveling to cause the body object to lodge
in the passageway near a predetermined location.
In yet another embodiment of the invention, a system that usable
with a well includes a casing string, a plurality of location
markers and a plug. The casing string is adapted to support a
wellbore of the well and includes a passageway. The locations
markers are deployed along the passageway. The plug travels
downhole untethered is the passageway and is adapted to sense
proximity to at least one of the location markers as the plug
travels downhole, estimate when the plug is to arrive near a
predetermined location in the well based at least in part on the
sensing of the location marker(s), and selectively expand its size
to cause the plug to become lodged in the passageway near the
predetermined location.
Advantages and other features of the invention will become apparent
from the following drawing, description and claims.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of a plug that may be deployed in a
well according to an embodiment of the invention.
FIG. 2 is an illustration of a wellbore depicting deployment of the
plug of FIG. 1 in the wellbore according to an embodiment of the
invention.
FIG. 3 is an illustration of the plug of FIG. 1 approaching a
location marker disposed along a passageway through which the plug
travels according to an embodiment of the invention.
FIG. 4 is amore detailed view of a section of the wellbore of FIG.
2 depicting the plug when lodged in a passageway of the wellbore
according to an embodiment of the invention.
FIG. 5 is an illustration of the wellbore depicting retrieval of
the plug according to an embodiment of the invention.
FIG. 6 is a perspective view of a portion of the plug illustrating
a blocker of the plug according to an embodiment of the
invention.
FIG. 7A is an illustration of a top view of the blocker of FIG. 6
in its radially expanded state according to an embodiment of the
invention.
FIG. 7B is a perspective view of the blocker of FIG. 6 in its
radially contracted state according to an embodiment of the
invention.
FIG. 8 is a flow diagram depicting a technique to deploy and use an
untethered plug in a well according to an embodiment of the
invention.
FIG. 9 is a flow diagram depicting a technique used by the plug to
autonomously control its operations in the well according to an
embodiment of the invention.
FIG. 10 is a schematic diagram of an architecture employed by the
plug according to an embodiment of the invention.
FIGS. 11, 12, 13, 14 and 15 depict a sequence in which the plug is
used to open and close flow control ports according to an
embodiment of the invention.
FIG. 16 is an illustration of a perforating gun assembly according
to an embodiment of the invention.
FIGS. 17, 18 and 19 are illustrations of a wellbore depicting, a
perforating operation conducted using, the perforating gun
apparatus of FIG. 16 according to an embodiment of the
invention.
FIG. 20 is an illustration of a wellbore depicting a system for
detecting location markers according to another embodiment of the
invention.
DETAILED DESCRIPTION
In accordance with embodiments of the invention, systems and
techniques are disclosed herein for purposes of autonomously
separating two zones inside a cylindrical environment of a well
using an untethered dart, or plug 10, which is depicted in FIG. 1.
As a non-limiting example, the cylindrical environment may be a
particular main or lateral wellbore segment of the well such that
the plug 10 may be conveyed downhole via fluid or a fluid flow
until the plug 10 is in the desired position or location where the
zonal isolation is to occur. In general, the plug 10 has modules,
which perform a variety of downhole tasks, such as the following:
1.) autonomously perceiving the location of the plug 10 with
respect to the downhole cylindrical environment as the plug 10 is
traveling through the downhole environment (via the plug's
perception module 26); 2.) autonomously radially expanding to
mechanically block and seal off the cylindrical environment at a
desired downhole location to separate two zones, including
anchoring of the plug 10 in place (via the plug's blocker 14); 3.)
autonomously actuating features of the plug 10 to perform the
above-described blocking, sealing and anchoring via the plugs
actuation module 18); and 4.) energizing the actuation 18 and
perception 26 modules (via the plugs energization module 22). As
described further herein, after performing its separation-of-zones
task, the plug 10 may, in accordance with some embodiments of the
invention, autonomously radially contract to remove the zonal
separation, which allows the plug 10 to be flowed in either
direction in the well for such purposes as forming zonal isolation
at another downhole location or possibly retrieving the plug 10 to
the Earth's surface.
As a non-limiting example, in accordance with some embodiments of
the invention, the plugs modules 14, 18, 22 and 26 may be contained
in a "pill shaped" housing 12 of the plug 10 to facilitate the
travel of the plug 10 inside the cylindrical environment. Thus, as
depicted in FIG. 1, the housing 12 of the plug 10 may, in general,
have rounded ends, facilitating backward and forward movement of
the plug throughout the cylindrical environment. In general, in its
initial state when deployed into the well, the plug 10 has a
cross-sectional area, which is smaller than the cross-sectional
area of the cylindrical environment through which the plug 10
travels. In this regard, the cylindrical environment has various
passageways into which the plug 10 may be deployed; and the plug
10, in its contracted, or unexpanded state, freely moves through
these passageways.
The plug 10, as further described herein, is constructed to
autonomously and selectively increase its cross-sectional area by
radially expanding its outer profile. This radial expansion blocks
further travel of the plug 10 through the cylindrical environment,
seals the cylindrical environment to create the zonal isolation and
anchors the plug 10 in place.
The expansion and contraction of the plug's cross-sectional area is
accomplished through the use of the blocker 14. In this manner,
when the plug 10 is in its radially contracted state (i.e., the
state of the plug 10 during its initial deployment), the blocker 14
is radially contracted such that the cross-sectional area of the
blacker 14 is substantially the same, in general, as the
cross-sectional area of the housing 10. The plug 10 is constructed
to selectively increase its cross-sectional area by actuating the
blocker 14 to expand the blocker's cross-sectional area to allow
the blocker 14 to thereby perform the above-described functions of
blocking, sealing and anchoring.
In general, the plug 10 increases its cross-sectional area to match
the cross-sectional area of the cylindrical environment for
purposes of creating zonal isolation at the desired downhole
location. Alternatively the plug 10 increases its crass-sectional
area to an extend that it in combination with another wellbore
element blocks the cross-sectional area of the cylindrical
environment for purposes of creating zonal isolation at the desired
downhole location (as shown for example in FIG. 4). After zonal
isolation is created, one or more operations (perforating,
fracturing, stimulation, etc.) may be conducted in the well, which
take advantage of the zonal isolation. At the conclusion of the
operation(s), it may be desirable to remove the zonal isolation.
Although conventionally, a plug is removed via another downhole
tool, such as a plug removal tool or drill, which may require
another trip into the well, the plug 10 is constructed to
autonomously undertake measures to facilitate its removal.
More specifically, in accordance with some embodiments of the
invention, when the zonal isolation provided by plug 10 is no
longer needed, the plug 10 may cause the blocker 14 to radially
contract so that the plug 10 may once again more freely through the
cylindrical environment. This permits the plug 10 to, as
non-limiting examples, be flowed to another stage of the well to
form zonal isolation at another downhole location, be flowed or
otherwise fall downwardly in the well without forming further
isolations, or be retrieved from the well. Alternatively, the plug
10 may remain in place and be removed by another downhole tool,
such as a milling head or a plug removal tool, depending on the
particular embodiment of the invention.
The plug 10 radially expands the blocker 14 in a controlled manner
for purposes of landing the plug 10 in the desired location of the
well. The perception module 26 allows the plug 10 to sense its
location inside the cylindrical environment so that the plug 10 may
cause the blocker 14 to expand at the appropriate time. In general,
the perception module 26 may be hardware circuitry-based, may be a
combination of hardware circuitry and software, etc. Regardless of
the particular implementation, the perception module 26 senses the
location of the plug 10 in the cylindrical environment, as well as
possibly one or more properties of the plug's movement (such as
velocity, for example), as the plug 10 travels through the
cylindrical environment.
Based on these gathered parameters, the perception module 26
interacts with the actuation module 18 of the plug 10 to
selectively radially expand the blocker 14 for purposes of creating
the zonal isolation at the desired location in the well. In
general, the actuation module 18 may include a motor, such as an
electrical or hydraulic motor, which actuates the blocker 14, as
further described below. The power to drive this actuation is
supplied by the energization module 22, which may be a battery, a
hydraulic source, a fuel cell, etc., depending on the particular
implementation. The power to actuate can be hydrostatic pressure.
The signal to actuate would release hydrostatic pressure (via
electric, rupture disc as an example) in to enter a chamber that
was at a lower pressure.
In accordance with some embodiments of the invention, the plug 10
determines its downhole position by sensing proximity of the plug
10 to landmarks, or locations markers, which are spatially
distributed in the well at various locations in the cylindrical
environment. As a more specific example, FIG. 2 depicts an
exemplary cylindrical environment in which the plug 10 may be
deployed, in accordance with some embodiments of the invention. It
is noted that this environment may be part of a land-based well or
a subsea well, depending on the particular implementation. For this
example, the cylindrical environment is formed from a casing string
54 that, in general, lines and supports a wellbore 50 that extends
through a surrounding formation 40. The casing string 54, in
general, defines an interior passageway through which the plug 10
may pass in a relatively unobstructed manner when the plug 10 is in
its contracted, or unexpanded state. Alternatively embodiments of
the invention may be used in an uncased wellbore environment.
In general, the FIG. 2 depicts the use of a flow F (created by a
surface pump, for example) to move the plug 10 toward the heel of
the illustrated wellbore 50. In FIG. 2, the reference numeral "10'"
is used to depict the various positions of the plug to along its
path inside the casing string 54. For this particular example, to
allow the plug 10 to autonomously determine its position as well as
one or more propagation characteristics associated with the
movement of the plug 10, the casing string 54 includes exemplary
location markers 60, 62 and 64.
Each location marker 60, 62 and 64 for this example introduces a
cross-sectional restriction through which the plug 10 is sized to
pass through, if the blocker 14 is in its retracted state. When the
blocker 14 of the plug 10 radially expands, the plug's cross
section is larger than the cross section of the marker's
restriction, thereby causing the plug 10 to become lodged in the
restriction. It is noted that the restrictions may be spatially
separate from the location markers, in accordance with other
embodiments of the invention.
In general, the perception module 26 of the plug 10 senses the
location markers 60, 62 and 64, as the plug 10 approaches and
passes the markers on the plug's journey through the passageway of
the casing, string 54. By sensing when the plug 10 is near one of
the location markers, the plug 10 is able to determine the current
position of the plug 10, as well, as one or more propagation
characteristics of the plug 10, such as the plug's velocity. In
this manner, the distance between two location markers may be
known. Therefore, the plug 10 may be able to track its position
versus time, which allows the plug 10 to determine its velocity,
acceleration, etc. Based on this information, the plug 10 is
constructed to estimate an arrival time at the desired position of
the well at which the zonal isolation is to be created.
Alternatively, plug 10 expands immediately when sensing a signal
just above landing in restriction in 64.
For the example that is illustrated in FIG. 2, the plug 10 creates
the zonal isolation at location marker 54. Therefore, as a
non-limiting example, the plug 10 may, when passing near and by
upstream location markers, such as location markers 60 and 62,
develop and refine an estimate of the time at which the plug 10 is
expected to arrive at the location marker 64. Based on this
estimate, the plug 10 actuates the blocker 14 at the appropriate
time such that the plug 10 passes through the markers upstream of
the location marker 64 while lodging in the restriction created at
the location marker 64. Thus, for this example, the plug 10 may
begin expanding the blocker 14 after the plug 10 passes through the
landmark 60 while still retaining a sufficiently small
cross-sectional area to allow the plug 10 to pass through the
location marker 62. After passage through the location marker 62,
the plug 10 completes the radial expansion of the blocker 14 so
that the plug 10 is captured by the restriction in the location
marker 64.
Referring to FIG. 3 in conjunction with FIGS. 1 and 2, in
accordance with some embodiments of the invention, the perception
module 26 includes a radio frequency identification (RFID) reader,
which transmits radio frequency (RF) signals for purposes of
interrogating RFID tags 70 that are embedded in the location
markers. In accordance with some embodiments of the invention, each
RFID tag stores data indicative of an ID for the tag, which is
different from the IDs of the other tags (i.e., each ID is unique
with respect to the other IDs). Therefore, through the use of the
different IDs, the plug 10 is able to identify a specific location
marker and as such, identify the plug's location in the well.
Thus, the interrogation that is performed by the RFID reader
permits the plug 10 to determine when the plug 10 passes in
proximity to a given location marker, such as the location marker
60 depicted in FIG. 3. Based on the sensing of location markers as
the plug 10 passes through the markers, the plug 10 determines when
to selectively expand the blocker 14 to permit capture of the plug
10 in a restriction 65 of the location marker 64, as depicted in
FIG. 4 (which shows a more detailed view of section 100 of FIG.
2).
Other types of sensors and sensing systems (acoustic, optical,
etc.) may be used, in accordance with some embodiments of the
invention, fir purposes of allowing the plug 10 to sense proximity
to location markers in the well.
Referring back to FIG. 2, operations may be conducted in the well
after the plug lodges itself in the well at the location marker 64.
These operations, in general, include operations that involve
pressurizing the passageway of the casing 54 above the lodged plug
10. As described further below, exemplary operations include
operations to control the open and closed states of a valve,
operations to stimulate the well, operations to perform hydraulic
fracturing, operations to communicate chemicals into the well,
operations to fire a perforating gun assembly, etc. Moreover, due
to the ability of the plug 10 to radially expand and contract again
and again, the plug 10 may be reused to create additional zonal
isolations and thereby allow additional operations to be conducted,
without retrieving the plug 10 from the well.
Referring to FIG. 5, when the zonal isolation that is provided by
the radially expanded plug 10 is no longer needed, the plug 10
retracts its cross-sectional area h actuating the blocker 14 in a
manner that retracts the cross-sectional area of the plug 10 to
allow the plug 10 to be reverse flowed out of the well using a
reverse flow F, as depicted in FIG. 5. Alternatively, the plug 10
may be flowed, or otherwise fall, further into the well upon
retracting its cross-sectional area, in accordance with other
embodiments of the invention. Moreover, in accordance with yet
other embodiments of the invention, another type of system, such as
a milling, system, may be used to mill out the obstructed plug 10.
For example, for these embodiments of the invention, the housing 12
of the plug 10 may be constructed from a material, which is easily
milled by a milling system that is run downhole inside the casing
string 54. Other variations are contemplated and are within the
scope of the appended claims.
FIG. 6 depicts a perspective view of a portion of the plug,
illustrating the blocker 14 in accordance with some embodiments of
the invention. For this example, the blocker 14 three layers 200a,
200b and 200c that circumscribe the longitudinal axis of the plug
10. Referring to FIG. 7B in conjunction with FIG. 6, the layers
200a and 200c are angularly aligned with respect to each other
about the longitudinal axis; and the layer 200b, which is disposed
between the layers 200a and 200c, is rotated by 180 degrees about
the transverse axis (i.e., is "flipped over") relative to the
layers 200a and 200c. The layers 200a, 200b and 200c are, in
general, disposed between two plates 203 and 204 of the blocker 14.
As an example, the plate 203 may be fixed in position relative to
the actuation module 18. The other plate 204, in turn, may be
coupled to a shaft 209 that is rotated by the actuation module 18
in the appropriate clockwise or counterclockwise direction to
retract or expand the blocker 14.
Referring to FIG. 7A in conjunction with FIGS. 6 and 7B, in
accordance with some embodiments of the invention, pins 222 attach
fingers 220 (which may each be constructed from an elastomeric
material, as a nonlimiting example) of each layer 200 to the plate
203. In this manner, some of the pins 222 pivotably attach fingers
200 of the layers 200a, 200b and 200c together, and other pins 222
slidably attach the fingers 200 of the layers 200a, 200b and 200c
to spirally-extending grooves 208 of the plate 204. When the
blocker 14 is initially deployed downhole in its radially
contracted state, the fingers 220 are radially contracted, as
depicted in FIG. 7B. In accordance with an example implementation,
because pins 222 reside in the grooves 208 of the turning plate
204, the fingers 220 may be radially expanded (see FIG. 7A) and
radially contracted (see FIG. 7B), depending on whether the
actuation module 18 turns the shaft 209 in a clockwise or
counterclockwise direction.
In accordance with other embodiments of the invention, the blocker
14 may be replaced with a compliant mechanism, such as the one
described in U.S. Pat. No. 7,832,488, entitled, "ANCHORING SYSTEM
AND METHOD," which issued on Nov. 16, 2010, and is hereby
incorporated by reference in its entirety. In other embodiments of
the invention, the blocker 14 may be replaced with a deployable
structure similar to one of the deployable structures disclosed in
U.S. Pat. No. 7,896,088, entitled, "WELLSITE SYSTEMS UTILIZING
DEPLOYABLE STRUCTURE," which issued on Mar. 1, 2011, and is hereby
incorporated by reference in its entirety; U.S. Patent Application
Publication No. US 2009/0158674, entitled, "SYSTEM AND METHODS FOR
ACTUATING REVERSIBLY EXPANDABLE STRUCTURES," which was published on
Jun. 25, 2009, and is hereby incorporated by reference in its
entirety; and U.S. Patent Application Publication No. US
2010/0243274, entitled, "EXPANDABLE STRUCTURE FOR DEPLOYMENT IN A
WELL," which was published on Sep. 30, 2010, and is hereby
incorporated by reference in its entirety.
Referring to FIG. 8, thus, in general, a technique 280 may be used
to deploy an untethered autonomous plug in a well for purposes of
creating zonal isolation at a particular desired location in the
well. Pursuant to the technique 280, one or more location markers
are deployed in a passageway of the well, pursuant to block 282.
The untethered plug may then be deployed, pursuant to block 284 in
a given passageway of the well. The plug is used to estimate (block
286) the arrival time of the plug near a predetermined location in
the well based on the plug's sensing of one or more of the location
markers. The plug is then used, pursuant to block 288, to
selectively expand its size based on the estimated arrival time to
become lodged near the predetermined location. Location markers may
be assembled to the casing string at surface prior to running the
casing string into the ground, in accordance with exemplary
implementations
In accordance with some embodiments of the invention, the plug 10
remains in its radially expanded state for a predetermined time
interval for purposes of allowing one or more desired operations to
be conducted in the well, which take advantage of the zonal
isolation established, by the radially expanded plug 10. In this
manner, in accordance with some embodiments of the invention, the
plug 10 autonomously measures the time interval for creating the
zonal isolation. More specifically, the plug 10 may contain a timer
(a hardware timer or a software timer, as examples) that the plug
10 activates, or initializes, after the plug 10 radial expands the
blocker 10. The timer measures a time interval and generates an
alarm at the end of the measured time interval, which causes the
plug 10 radially contract the blocker 14, for purposes of
permitting the retrieval of the plug 10 or the further deployment
and possible reuse of the plug 10 at another location.
More specifically, in accordance with some embodiments of the
invention, the plug 10 performs a technique 300 depicted in FIG. 9
for purposes of controlling the radial expansion and contraction of
its cross-sectional area. Pursuant to the technique 300, the plug
10 transmits (block 304) at least one RE signal to interrogate the
closest location marker and based on these transmitted RF
signal(s), determines (diamond 308) whether the plug is
approaching, or is near another location marker. If so, the plug 10
determines (block 312) the position and velocity of the plug 10
based on the already detected location markers and correspondingly
updates (block 316) the estimated time of arrival at the desired
location in the well. If based on this estimated time of arrival,
the plug 10 determines (diamond 320) that the plug 10 needs to
expand, then the plug radially expands, pursuant to block 324.
Otherwise, control returns to block 304, in which the plug 10
senses any additional location markers. After the radial expansion
of the plug 10, the plug 10 waits for a predetermined time, in
accordance with some embodiments of the invention, to allow desired
operations to be conducted in the well, which rely on the zonal
isolation. Upon determining (diamond 330) that it is time to
contract, then the plug 10 radially contracts to allow its
retrieval from the well or its further deployment and possible
reuse at another location.
In accordance with other embodiments of the invention, the plug 10
determines whether the plug 10 needs to expand without estimating
the time at which the plug 10 is expected to arrive at the desired
location. For example, the plug 10 may expand based on sensing a
given location marker with knowledge that the given location marker
is near the predetermined desired location in the well. In this
manner, the given location marker may be next to the desired
location or may be, as other non-limiting examples, the last or
next-to-last location marker before the plug 10 reaches the desired
location. Thus, many variations are contemplated and are within the
scope of the appended claims.
In accordance with other embodiments of the invention, the plug 10
may communicate (via acoustic signals, fluid pressure signals,
electromagnetic signals, etc.) with the surface or other components
of the well for purposes of waiting for an instruction or command
for the plug 10 to radially contract. Thus, aspects of the plug's
operation may be controlled by wireless signaling initiated
downhole or initiated from the Earth surface of the well.
Therefore, many variations are contemplated and are within the
scope of the appended claims.
As a general, non-limiting example, FIG. 10 depicts a possible
architecture 350 employed by the plug 10 in accordance with some
embodiments of the invention. In general, the architecture 350
includes a processor 352 (one or more microcontrollers, central
processing units (CPUs), etc.), which execute one or more sets of
program instruction 360 that are stored in a memory 356. In
general, the architecture 350 includes a bus structure 364, which
allows the processor 352 to access a motor driver 368 for purposes
of driving a motor 370 to selectively expand and contract the
blocker 14. Moreover, in accordance with some embodiments of the
invention, the processor 352, by executing the program instructions
360, operates an RFID reader 374 for purposes of generating RF
signals, via an antenna 378 for purposes of interrogating RFID tags
that are disposed at the location markers in the well and receiving
corresponding signals (via the antenna 378, or another antenna, for
example) from an interrogated RFID tags. Based on this instruction,
the processor 352 may sense proximity to a given location marker.
As a non-limiting example, each RFID (in the location marker) may
store an ID that is distinct from the IDs stored by the other RFID
tags to allow the processor 352 to determine the location of the
plug 10, the velocity of the plug 10, etc. The processor 352 may,
for example, access a table of locations (stored in the memory 356,
for example), which is indexed by IDs to allow the processor 352 to
correlate a given location marker (as indicated by a specific
ID.)
As a non-limiting example, FIGS. 11, 12, 13, 14 and 15 depicts an
exemplar, repeatable downhole operation that may be performed using
the plug 10, in accordance with some embodiments of the invention.
For this example, the plug 10 is radially expanded to lodge the
plug 10 within a restricted passageway of a control sleeve 408 of a
sleeve valve 400 (see FIG. 11). Thus, fluid pressure may be
increased to shift the control sleeve 408 to open fluid
communication ports 404 of the valve 400 to communicate a
circulation flow 409, as depicted in FIG. 12. Likewise, flow may be
reversed in the opposite direction for purposes of using the plug
10 to shift the control sleeve 408 in the opposite direction to
close the fluid communication through the ports 404, as depicted in
FIG. 13. As shown in FIG. 14, the plug 10 may then be radially
contracted to allow the plug 10 to be moved, in either direction in
the well (either by a forward flow, a reverse flow F, as depicted
in FIG. 15, or a gravity caused free falling) for such purposes as
operating another valve in the well or possibly retrieving the plug
10 to the Earth's surface.
As an example of another use of the plug 10, the plug may be part
of a perforating gun assembly 450, in accordance with some
embodiments of the invention. For this non-limiting example, in
general, the plug 10 may form the nose of the perforating gun
assembly 450, which also includes a perforating gun substring 454
that is attached to the back end of the plug 10a and contains
perforating charges 455, such as shaped charges. The perforating
gun assembly 450 may be flowed in an untethered manner into a
downhole cylindrical environment for purposes of performing a
perforating operation at a desired downhole location.
As a more specific example, FIG. 17 depicts an exemplary wellbore
500 that is cased by a casing string 540 that, in general, lines
and supports the wellbore 500 against a surrounding formation 550.
For this example, the perforating, gun assembly 450 travels through
the interior passageway of the casing string 540 via a flow F.
Thus, FIG. 17 depicts various intermediate positions 450' of the
perforating gun assembly 450 as it travels in its radially
contracted state through the passageway of the casing string 540.
In its travel, the perforating gun assembly 450 passes and senses
at least one location marker, such as marker 560 (containing an
RFID tag 570, for example), and based on the detected marker(s),
the plug 10 radially expands at the appropriate time so that the
perforating gun assembly 450 becomes lodged at a location marker
564. Thus, at the location of the perforating gun assembly 450
depicted in FIG. 17, perforating operations are to be
conducted.
Referring to FIG. 18, for this example, the perforating gun 454
(see FIG. 16) may be a pressure actuated perforating (TCP) gun, and
due to the zonal isolation created by the plug 10, fluid pressure
inside the casing string 540 may be increased to fire the gun's
perforating charges 455. The perforating operation perforates the
surrounding casing string 540 and produces corresponding
perforation tunnels 580 into the surrounding formation 550. At the
conclusion of the perforating operation, the plug 10 radially
contract to allow the perforating gun assembly 450 to be flowed in
either direction in the well (via a reverse flow F, as depicted in
FIG. 19) for such purposes as using unfired charges of the
perforating gun assembly 450 to perforate another zone or possibly
retrieving the perforating gun assembly 450 to the Earth's
surface.
Other embodiments are contemplated and are within the scope of the
appended claims. For example, referring to FIG. 20, in accordance
with some embodiments of the invention, an untethered plug 600 may
generally contain the features of the plugs disclosed herein,
except that the plug 600 has a perception module 620 (replacing the
perception module 26) that senses a given location marker by
detecting a change in an electromagnetic field signature, which is
caused by the presence of the location marker. In this manner, the
perception module 620 contains a signal generator 624 (a radio
frequency (RF) generator, for example), which generates a signal
(an RF signal, for example) that drives an antenna 628 to produce a
time changing electromagnetic field. A location marker 656 (in a
casing string 654) contains an inductor-capacitor tag, or "LC tag,
that is formed from a capacitor 604 and an inductor that influences
this electromagnetic field. The inductor may be formed, for
example, from a coil 600 of multiple windings of a wire about the
inner diameter of the casing, string 654 such that the coil 600
circumscribes the longitudinal axis of the string 654.
The inductor and the capacitor 604 of the location marker 656 may
be serially coupled together and are constructed to influence the
signature of the signal that is produced by the signal generator
624. In other embodiments, the inductor and the capacitor 604 may
be coupled together in parallel. When the plug 600 is in the
vicinity of the location marker 656, the electromagnetic field that
emanates from the plug's antenna 628 passes through the coil 600 to
effectively couple the inductor and capacitor 504 to the signal
generator 624 and change the signature of the signal that the
signal generator 624 generates to drive the antenna 628. A detector
632 of the perception module 620 monitors the signal that is
produced by the signal generator 624 for purposes of detecting a
signature that indicates that the plug 600 is passing in the
proximity of the location marker 656. As non-limiting examples, the
signature may be associated with a particular amplitude, amplitude
change, frequency, frequency change, spectral content, spectral
content change or a combination of one or more of these parameters.
Thus, the detector 632 may contain one or more filters,
comparators, spectral analysis circuits, etc., to detect the
predetermined signature, depending on the particular
implementation.
In accordance with some embodiments of the invention, upon
detecting the signature, the detector 632 increments a counter 636
(of the perception module 620), which keeps track of the number of
detected location markers 656. In this manner, in accordance with
some embodiments of the invention, the perception module 620
initiates deployment of the blocker 14 in response to the counter
636 indicating, that a predetermined number of the location markers
656 have been detected, in this manner, in accordance with some
embodiments of the invention, the LC "tags" in the casing 654 all
have the exact same resonance frequency (signature), so the plug
600 counts identical LC tags so that the plug 600 opens the blocker
14 after the plug 600 passes N-1 markers so that the plug 600 locks
into the Nth marker. Other variations are contemplated, however.
For example, in accordance with other embodiments of the invention,
each location marker 656 employs different a different combination
of inductance and capacitance. Therefore, the signatures produced
by the location markers 656 may be distinctly different for
purposes of permitting the detector 632 to specifically identify
each location maker 656.
As an example of another embodiment of the invention, the layers
200a, 200b and 200c (see FIGS. 6, 7A and 7B) of the blocker 14 may
be biased by resilient members to retract (FIG. 7B). The layers
200a, 200h and 200c may be radially expanded and retracted using a
tapered plunger that extends through the central openings of the
layers 200a, 200b and 200c to radially expand the layers 200a, 200b
and 200c (see FIG. 7A) and retracts from the central openings to
allow the layers 200a, 200b and 200c to retract (FIG. 7B). The
actuation module 18, for this embodiment, contains a linear motor
that is connected to the tapered plunger to selectively drive the
plunger in and out of the central openings of the layers 200a, 200b
and 200c, depending on whether or not the blocker 14 is to be
radially expanded.
While the present invention has been described with respect to a
limited number of embodiments, those skilled in the art, having the
benefit of this disclosure, will appreciate numerous modifications
and variations therefrom. It is intended that the appended claims
cover all such modifications and variations as fall within the true
spirit and scope of this present invention.
* * * * *